Phagraphene nanoribbons: half-metallicity and magnetic phase transition by functional groups and electric field

Abstract

Magnetic nanomaterials with the desirable nature are the basis for developing future spintronic devices, and research for them is of fundamental interest. Here, we explore the realization of half-metallicity and magnetic phase transition for phagraphene nanoribbons in virtue of functional groups (OH and CN) with different coverage fractions and external electric fields. The first-principles calculations show that a single-edge CN functionalization only makes a intrinsic spin-degenerate semiconducting ribbon converted to a quasi-metal or metal, while a single-edge OH modification leads to an occurrence of the half-semiconducting nature regardless of the coverage fraction of groups. Interestingly, the half-metal behavior for the CN and OH double-edge modified ribbons can be achieved either in the zero-electric-field intrinsic state for most of functionalized systems or at a very low electric field, 0.1 V Å. More importantly, the observed critical electric field for the transition from ferromagnetic to nonmagnetic phase is lowered significantly almost for all systems, this benefits to design a low electric-field-controlling magnetic switch which can reversibly work between both magnetic and nonmagnetic states. The calculated Gibbs free energy confirms that the group-modified ribbons generally hold a more favorable energy stability in most of the cases, facilitating likely experimental realization.

Rich magnetic phase transitions and completely dual-spin polarization of zigzag PC3 nanoribbons under uniaxial strain

“…1 As a hot field of current research, spintronic devices show great application potential. [2][3][4] Moreover, the accelerative development of science and technology requires that electronic devices must be miniaturized and highly integrated, thus predicting highly spinpolarized nanoscale spintronic materials becomes a primary and arduous task. [5][6][7] It is universally acknowledged that halfmetal magnets (HMM) with 100% spin polarization have always been typical materials for spintronics.…”

Electronic, optical, vibrational and thermodynamic properties of phaBN structure: a first principles study

“…This flat carbon allotrope is energetically comparable to graphene and more favorable than other carbon allotropes Email address: jonas.lima@ufrpe.br (Jonas R. F. Lima) proposed in previous works due to its hybridization in sp 2 . Since its proposal, phagraphene attracted great deal of attention, which can be confirmed by the number of works addressed to this subject [20,21,22,23,24,25,26,27,28,29,30,31,32,33,34,35,36].…”

Single-layer PtSe2 adsorbed with non-metallic atoms: geometrical, mechanical, electronic and optical properties and strain effects

“…The first-principles calculation software Atomistix ToolKit (ATK) [26][27][28][29] based on density functional theory (DFT) was used for all calculations presented in this work. To solve the Kohn-Sham equation, the Perdew-Burke-Ernzerhof (PBE) functional in the framework of generalized gradient approximation (GGA) was employed as the exchange correlation potential, the linear combination of atomic orbital (LCAO) was used to expand the wave function of valence electrons, and PseudoDojo was utilized to describe interactions between the atomic core and valence electrons.…”